Every mesh AP will still get an IP address. You can ping the IP address of each AP in the mesh to observe some latency. You can establish throughput by connecting to the mesh AP as a client and running a throughput test. You can see signal strength by doing a "show ap mesh topology" command and seeing the RSSI column:
(ArubaM3) #show ap mesh topology
Mesh Cluster Name: aruba-mesh
-----------------------------
Name Mesh Role Parent Path Cost Node Cost Link Cost Hop Count RSSI Rate Tx/Rx Last Update Uplink Age #Children
---- --------- ------ --------- --------- --------- --------- ---- ---------- ----------- ---------- ---------
Bridge-CAP Portal (N) - 3 1 0 0 0 - 5m:54s 1d:3h:39m:10s 1
MeshPoint Point Bridge-CAP 4 0 0 1 24 36/54 7m:5s 1d:3h:20m:17s 0
Total APs :2
(R): Recovery AP. (N): 11N Enabled. For Portals 'Uplink Age' equals uptime.